Factorization

[Wolfgang Abele]

Can anybody tell me how to include Stefan's conversion routines from gtybalt 
in GiNaC? Should I write a symbolic function or add a class or copy the 
routines in normal.cpp and normal.h and 'make' GiNaC again? (The latter won't 
work with me, though, because I get those ginsh error messages no matter if I 
use readline 4.1 or 4.2 (the bug is supposedly fixed in 4.2))

>>Hence, the general mutivariate stuff would be what is really suited for
>>GiNaC.  But if you think that doing univariate first is the right thing to
>>do in order to get started with factorization
Multivariate factorization is always reduced to univariate factorization. So 
you've got to have it in GiNaC, even if it's just a subroutine.

>>there is currently no class that represents algebraic
>>extensions.  Representation is another no-brainer, as far as I can see,
>>since it should just hold one expression which represents the zero. 
Yes, that's right. Computing the polynomial remainder of a division is 
already implemented, isn't it? Later we also may need a routine to compute 
the primitive element for a tower of extensions.

>>our GCD routines are not prepared for extensions.  Is that needed?
We would need one as a subroutine for Trager. Trager, by the way, can handle 
multivariate polynomials as well.
>> Is it difficult???applies to
The algorithm isn't, which doesn't imply that's it's also easy to implement, 
at least not as far as I'm concerned.

Servus, Wolfgang